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SHORROCK SUPERCHARGER C75B
thunderace - 16/10/06 at 12:52 PM

hi im thinking of fitting a supercharger to my xflow 711 1700cc +90 1300 pistons big valve head ,,,
would it be a good idear to fit one ,at the moment i have twin 40s fast road cam new waterpump fuel pump and aldon dizzy ect.,,
would the engine handle the exstra power as its about the 135 bhp at the moment i hope
but i always like the idear of fitting a supercharger. Rescued attachment Copy of DSCF0796.JPG
Rescued attachment Copy of DSCF0796.JPG


graememk - 16/10/06 at 02:44 PM

do it lol


02GF74 - 16/10/06 at 03:10 PM

well, surprisingly to me at least, it has been done;


a quick search threw up only 1 link.

http://www.ferretteria.co.uk/Technical.htm

I;ve no idea what popwere you would see ; guessing around 200 bhp so would need the strong block 711M or the other stronger one and strong crank/rods. (maybe you have those already).

So it sounds like a good plan - keep us informed how you progress!


John Bonnett - 16/10/06 at 03:36 PM

Hi, Seeing your post has taken me right back to the 60s when I fitted a C75B to a 1172 Dellow back in the days when Allard sold them complete with blow-off valves boost gauges pipework and all the bits you needed to complete the installation.

Generally the power increase was in the range of 30% but I think you will need to lower the compression which you can probably do with alternative pistons. The blower takes an oil feed direct from the engine, I think I teed off the oil pressure sender and this is a total loss system with the oil being combusted with the fuel. We are only talking a small amount here and will not hugely affect oil consumption. The great thing about a supercharged engine is the amount of power increase from nearly no revs. It will be a great project and I for one will be very interested to hear how you get on.
alb
John


MikeRJ - 16/10/06 at 04:34 PM

You will definately need to lower the compression ratio to be able to run any reasonable amount of boost. The fast road cam should be ok, unless it has significant overlap which can cause low speed running problems with a supercharger.

Unfortunately, when you tune a normaly aspirated engine for significant power increase, you are invariably moving in the wrong direction for converting it to forced induction at a later stage.


irvined - 16/10/06 at 06:38 PM

As has been said, you will probably want to lower the compression ratio somewhat, you can possibly do this by fitting thicker head gaskets, you might be able to machine the pistons down a little too.

Personally I'd go for it, the sound of forced induction is amazing, sadly you might end up having to undo some of the hard work you've done to boost the performance already.